An Experimental Study on Behaviour of GSB Layer by Utilization of Granulated Sub Base, Crumb Rubber and Pond Ash

Subbase is a layer of aggregate material laid on the subgrade, on which the base course layer is located. Subbase is often the main load-bearing layer of the pavement. Its role is to spread the load evenly over the subgrade. The quality of subbase is very important for the useful life of the road. Subbase is prepared according to the MORTH norms. Red soils denote the second largest soil group available in India. The handling of Red soil is a difficult task for highway engineer to construct the road due to several reasons, so various soil modification techniques are tried to enhance the properties of soil. Granulated blast furnace slag (GBFS) is major by-product of steel plants, which causes the environmental pollution and also Crumb Rubber (CR) is a leftover product of castoff rubber tyres. Both of these waste products causes the disposal problem. In this study these materials are used as a reinforcing material for subbase layer. This study presents the result of experimental investigation on the influence of Pond ash (PA) on the index properties of Red soil. The aggregates which are used in subbase level can be replaced with varying percentages GBFS and CR separately.